1. Field of the Invention
This invention relates to a scanning illuminator suitable for use in high speed copying machines.
2. Description of the Prior Art
In the prior art slit-exposure type copying machines, it is known that two sources of light are symmetrically disposed adjacent to the opposite end of an original supporting area, the light beams from the respective light sources being progressively reflected toward the surface of an original to be copied for scanning it in a slit-exposure manner. However, it is also known that they have disadvantages in that the incident angle at the opposite end of the original is increased to reduce the illumination efficiency and that the rotary mirrors do not deal with any wrong positioning of optical systems and any deviation of light sources out of given positions. In other words, the prior art slit-exposure type copying machines have no flexibility. If a source of light is positioned at a wrong location, for example, upon exchanging, the light beam therefrom would be changed in incident-angle to the rotary mirror so as to deviate the scanned area on the surface of the original.